The second modification is to conduct an individualized preference assessment to identify types of food and leisure items a given child prefers. This is done by having the child select items from an array (items selected based on direct observations of child and parent/teacher report) and allowing him/her access to the chosen item for a brief period of time. This will generate a list of preferred items/activities ranked in order of relative preference. Subsequently, the highest ranked items from the preference assessment will be arranged as reinforcers for continence, appropriate eliminations, and self-initiations. A third modification is to combine the above modifications to determine whether a combination of toilet training procedures enhances toileting performance (as compare to the implementation of individual toilet training procedures). This modification will be conducted while children wear underwear.